The movie came out in 1984, and Egon was sporting some kind of tall puffy 'fro, which along with his glasses, made him look like a typical geek. In fact, when you say the word geek, many people think of Egon. He was like the first funny good guy geek in a movie.

A lot of his lines were ad-libbed in Ghostbusters, like
"[When I tried to drill a hole in my head], that would have worked if you hadn't tried to stop me!"
"When I was a kid, I had part of a slinky, but I straightened it."